The stock upper control arm measures approximately 9.5 inches between the bolt centers with a two-piece driveshaft. When we switched to the one-piece aluminum driveshaft, it significantly changed the pinion angle of the rearend to the driveshaft. This added adjustability is critical if you decide to lower your Steed later. Pre-adjust the arm to 9.25 inches between the bolt center; keep the spacing between the nuts even or you will limit adjustability. Do not final-tighten it until the pinion angle is checked.